1. Field
The subject matter disclosed herein relates to homography evaluation involving mobile devices
2. Information
Many mobile communication devices include a camera capable of capturing high-quality still images and live video sequences. In many situations, a user may wish to augment live camera images with virtual objects that do not exist or are not visible in a captured image. These situations may include animating avatars and other three-dimensional objects in games, live technical manuals that describe complex machinery, and many others.
Prior to augmenting a video image, some form of object detection may be performed on a captured video stream. Augmentation may involve extracting features from a video stream that may be used to recognize an object from similar and/or different perspectives. If a sufficient number of features satisfying certain criteria are found to be common to both an object in a video stream and an object retrieved from a database, a determination may be made that a particular object has been detected in a captured video image. Upon detection of the object in an image, augmentation of the image may take place. As a perspective of the video scene changes, the perspective of a virtual object added to the video scene may also change as though the virtual object was present in the originally-captured scene.
However, detecting an object in a video stream may involve extensive processing to establish homography between a reference object image and an image extracted from a video stream. Additionally, even if homography between a reference image and the extracted image is found, the augmentation may not be realistic if the extracted homography does not meet certain criteria. This may be especially problematic while attempting to augment a scene in three dimensions, as the camera angle changes relative to detected objects in a captured two-dimensional image.